<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <link rel="import" href="./index.js">
  <title>Document</title>
  <style>
    body {
      height: 3000px;
    }
    .demo {
      position: absolute;
      top: 1000px;
      width: 100px;
      height: 100px;
      background-color: orangered;
    }
  </style>
</head>
<body>
  <div class="demo"></div>
</body>
<script src="./index.js" type="module"></script>
</html>